📇 CPE Index

The index module provides CPEIndex, a concurrent-safe in-memory index over a slice of CPEs offering O(1) average lookups by vendor, product, part, or PURL. It is designed for batch scanning scenarios where the same set of CPEs is queried repeatedly. A sync.RWMutex guards all maps, so reads and writes can proceed concurrently.

Type: CPEIndex

type CPEIndex struct {
    mu        sync.RWMutex         // guards all map fields
    byVendor  map[string][]*CPE    // index by vendor name
    byProduct map[string][]*CPE    // index by product name
    byPart    map[string][]*CPE    // index by part (a/h/o)
    byPURL    map[string]*CPE      // index by PURL string
    all       []*CPE               // all CPEs in the index
}

All fields are unexported. CPEs whose vendor or product is empty or equals ValueANY are not added to those specific indexes (but remain in all); PURL mappings are added explicitly via IndexPURL.

🆕 NewCPEIndex

func NewCPEIndex(cpes []*CPE) *CPEIndex

Creates a new index from a CPE slice, building the vendor, product, and part indexes. nil entries in cpes are skipped. The byPURL map starts empty (use IndexPURL to populate it).

Parameter	Type	Description
cpes	[]*CPE	Initial CPEs to index

Return	Type	Description
#1	*CPEIndex	A new, populated index

cpes, _ := cpeskills.NewFileStorage("/tmp/cpe-data", false).SearchCPE(nil, nil)
idx := cpeskills.NewCPEIndex(cpes)
fmt.Println(idx.Size())

🔍 Lookup

func (idx *CPEIndex) Lookup(criteria *CPE) []*CPE

Returns CPEs matching criteria using the fastest available index. Preference order: vendor (then further filtered by product), product, part. If criteria is nil or has no usable field, a copy of all CPEs is returned. Thread-safe for concurrent reads.

Parameter	Type	Description
Receiver	*CPEIndex	The index
criteria	*CPE	Match criteria; nil returns all

Return	Type	Description
#1	[]*CPE	Matching CPEs (or a copy of all)

results := idx.Lookup(&cpeskills.CPE{
    Vendor:      cpeskills.Vendor("apache"),
    ProductName: cpeskills.Product("log4j"),
})

🔍 LookupByPURL

func (idx *CPEIndex) LookupByPURL(purl *PackageURL) *CPE

Returns the CPE mapped to purl, or nil if none. Thread-safe for concurrent reads.

Parameter	Type	Description
Receiver	*CPEIndex	The index
purl	*PackageURL	The package URL to look up

Return	Type	Description
#1	*CPE	The mapped CPE, or nil

cpe := idx.LookupByPURL(purl)

➕ IndexPURL

func (idx *CPEIndex) IndexPURL(purl *PackageURL, cpe *CPE)

Maps purl (by its string form) to cpe, overwriting any prior mapping. No-ops if either argument is nil. Thread-safe for concurrent writes.

Parameter	Type	Description
Receiver	*CPEIndex	The index
purl	*PackageURL	The package URL
cpe	*CPE	The CPE to associate

Return	Type	Description
(none)

idx.IndexPURL(purl, cpe)

📏 Size

func (idx *CPEIndex) Size() int

Returns the number of CPEs in the index (the length of all).

Parameter	Type	Description
Receiver	*CPEIndex	The index

Return	Type	Description
#1	int	Number of indexed CPEs

fmt.Println(idx.Size())

📋 All

func (idx *CPEIndex) All() []*CPE

Returns a copy of all CPEs in the index. The returned slice is safe to mutate without affecting the index.

Parameter	Type	Description
Receiver	*CPEIndex	The index

Return	Type	Description
#1	[]*CPE	A copy of all indexed CPEs

all := idx.All()

🏷️ GetByVendor

func (idx *CPEIndex) GetByVendor(vendor string) []*CPE

Returns all CPEs indexed under vendor (returns the underlying slice directly, not a copy).

Parameter	Type	Description
Receiver	*CPEIndex	The index
vendor	string	Vendor name

Return	Type	Description
#1	[]*CPE	CPEs for that vendor (nil if none)

cpes := idx.GetByVendor("apache")

🏷️ GetByProduct

func (idx *CPEIndex) GetByProduct(product string) []*CPE

Returns all CPEs indexed under product (returns the underlying slice directly, not a copy).

Parameter	Type	Description
Receiver	*CPEIndex	The index
product	string	Product name

Return	Type	Description
#1	[]*CPE	CPEs for that product (nil if none)

cpes := idx.GetByProduct("log4j")

🏷️ GetByPart

func (idx *CPEIndex) GetByPart(part string) []*CPE

Returns all CPEs indexed under part (the short part name: a, h, or o).

Parameter	Type	Description
Receiver	*CPEIndex	The index
part	string	Short part name

Return	Type	Description
#1	[]*CPE	CPEs for that part (nil if none)

apps := idx.GetByPart("a")

📊 VendorCount

func (idx *CPEIndex) VendorCount() int

Returns the number of distinct vendors in the index.

Parameter	Type	Description
Receiver	*CPEIndex	The index

Return	Type	Description
#1	int	Distinct vendor count

fmt.Println(idx.VendorCount())

📊 ProductCount

func (idx *CPEIndex) ProductCount() int

Returns the number of distinct products in the index.

Parameter	Type	Description
Receiver	*CPEIndex	The index

Return	Type	Description
#1	int	Distinct product count

fmt.Println(idx.ProductCount())

➕ Add

func (idx *CPEIndex) Add(cpe *CPE)

Adds cpe to the index: appended to all and inserted into the vendor, product, and part indexes (subject to the empty/ValueANY rule). No-ops if cpe is nil. Thread-safe for concurrent writes.

Parameter	Type	Description
Receiver	*CPEIndex	The index
cpe	*CPE	The CPE to add

Return	Type	Description
(none)

idx.Add(cpe)

➖ Remove

func (idx *CPEIndex) Remove(cpeURI string)

Removes the CPE whose Cpe23 equals cpeURI from all, the vendor, product, and PURL indexes. No-ops if not found. Thread-safe for concurrent writes.

Parameter	Type	Description
Receiver	*CPEIndex	The index
cpeURI	string	CPE 2.3 URI of the CPE to remove

Return	Type	Description
(none)

idx.Remove("cpe:2.3:a:apache:log4j:2.0:*:*:*:*:*:*:*")

🧹 Clear

func (idx *CPEIndex) Clear()

Removes all entries from every index, resetting all maps and setting all to nil.

Parameter	Type	Description
Receiver	*CPEIndex	The index

Return	Type	Description
(none)

idx.Clear()

🧭 CPEIndex 索引结构